Sewing machine having a function for damping the vibration of embroidering frame and an embroidering frame having a function for damping the vibration thereof

ABSTRACT

A sewing machine having an embroidery stitching function is disclosed, the sewing machine comprising a drive mechanism for driving an embroidering frame B, a means for holding the embroidering frame B and operatively connected to the drive mechanism to be driven thereby to move the embroidering frame B in X-Y direction relative to a vertically reciprocating needle on the surface of a machine bed, and a means for normally pressing the embroidering frame B against the surface of the machine bed with an optimal force to absorb the vibrations of the embroidering frame B which may be caused during embroidery stitching operation, thereby to prevent the embroidering frame B from vibration and/or moving fup from the surface of the machine bed to secure a stabilized embroidery stitching operation.

BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT

[0001] 1. Field of the Invention

[0002] The present invention relates to a sewing machine having an embroidery stitching function, and more particularly relates to a sewing machine having a function for damping the vibration of an embroidering frame which may be produced during embroidery stitching operation and further relates to an embroidering frame having a function for damping the vibration of itself, so that the embroidery stitching operation may be performed smoothly and steadily while the embroidering frame is held as being stabilized on the sewing machine bed.

[0003] 2. Prior Art

[0004] Recently the sewing machine having a drive mechanism for driving an embroidering frame has been generally used. The drive mechanism includes a carriage for removably holding the embroidering frame. The carriage is partly extended out of the sewing machine frame and driven into and out of the sewing machine frame so as to be moved in X-Y direction, thereby to move the embroidering frame in X-Y direction accordingly relative to a vertically reciprocating needle on the surface of a machine bed. Thus the embroidery stitching operation is performed.

[0005] In case the embroidering frame is moved in X-Y direction on the surface of the machine bed, it is required that the embroidering frame is moved in a stabilized condition wherein the embroidering frame is constantly in close contact with the surface of the machine bed. According to the prior art, as shown in FIG. 7(a), the embroidering frame f mounted to the carriage c will often fail to correctly contact the surface of the machine bed b and float up from the surface of the machine bed b. This is because the precision is not sufficient in the parts of the drive mechanism and /or in the assembly thereof, or in the connecting part between the embroidering frame f and the carriage c.

[0006] On the other hand, as shown in FIG. 7(b), since the embroidering frame f is generally rigid and fails to have a movable part at the arm portion thereof by which the embroidering frame f is mounted to the carriage c, the embroidering frame f is often pressed against the surface of the machine bed b with a strong force which will produce a friction between the embroidering frame f and the surface of the machine bed b, thus hindering the movement of the embroidering frame f.

[0007] Further, the driving movement of a drive motor and the resultant operation movement of the embroidering frame drive mechanism may be transmitted to the embroidering frame to vibrate the same. This will often hinder the smooth and steady movement of the embroidering frame. Further, the vertically reciprocating needle will vibrate the embroidering frame up and down with the instantaneous force given to the cloth held by the same as the needle is moved up through the cloth. In any events, such vibrations will give adverse influence to formation of stitches and to the stitched result of embroidery patterns.

OBJECTS OF THE INVENTION

[0008] It is, therefore, a primary object of the invention to provide an embroidery sewing machine having a function for damping the vibrations of embroidering frame which may be caused during embroidery stitching operation.

[0009] It is another object of the invention to provide an embroidery sewing machine having a function for absorbing the vibrations of embroidering frame which may be caused during embroidery stitching operation.

[0010] It is another object of the invention to provide an embroidery sewing machine having a function for elastically pressing the embroidering frame against the surface of machine bed with an optimal force.

[0011] It is another object of the invention to provide a vibration damping or absorbing means which is simple in structure and in smooth in operation.

[0012] It is another object of the invention to provide elastic means in connection with the carriage for pivotally holding the embroidering frame to normally press the embroidering frame against the surface of machine bed.

[0013] It is another object of the invention to provide a means for regulating the pivotal movement of the embroidering frame to normally maintain an optimal contact between the embroidering frame and the surface of machine bed.

[0014] It is another object of the invention to provide elastic means at a proper part of the embroidering frame to normally deflect the embroidering frame to the surface of machine bed.

[0015] It is still another object of the invention to provide the carriage with an inclined surface as is progressively lowered towards the machine bed so as to normally deflect the embroidering frame to the surface of machine bed.

[0016] The other objects and advantages will be apparent in the following detailed description of the invention.

SUMMARY OF THE INVENTION

[0017] For attaining the objects, the invention substantially comprises an embroidering frame having a cloth held thereon to be stitched, a drive mechanism for moving the embroidering frame, means including a carriage for holding the embroidering frame and operatively connected to the drive mechanism to be moved thereby to move the embroidering frame in X-Y direction relative to a vertically reciprocating needle on the surface of a machine bed, and means for absorbing the vibrations of the embroidering frame which may be caused during embroidery stitching operation, wherein the vibration absorbing means includes a spring member provided in connection with the carriage or in connection with the embroidering frame so as to yieldably press the embroidering frame against the surface of the machine bed, and wherein the carriage is provided with an inclined surface as is progressively lowered towards the machine bed to have the embroidering frame mounted thereto such that the embroidering frame may yieldably deflect up and down. The invention further comprises means for regulating the angular movement of the embroidering frame to normally maintain an optimal contact between the embroidering frame and the surface of machine bed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a side elevational view of a sewing machine having essential parts of the invention provided therewith;

[0019]FIG. 2

[0020] (a) is a perspective view of the essential parts of a carriage of the invention for holding an embroidering frame;

[0021] (b) is a side elevational view of the essential parts of the carriage shown in vertical section;

[0022] (c) is a front elevational view of the essential parts of the carriage partly shown in vertical section;

[0023]FIG. 3

[0024] (a) is an enlarged side elevational view of the essential parts of the carriage shown in vertical section as partly moved in one direction;

[0025] (b) is an enlarged side elevational view of the essential parts of the carriage shown in vertical section as partly moved in the opposite direction;

[0026] (c) is another enlarged side elevational view of the essential parts of the carriage of (a) shown in vertical section to show the movement of the parts regulated in one direction;

[0027] (d) is another enlarged side elevational view of the essential parts of the carriage of (b) shown in vertical section to show the movement of the parts regulated in the opposite direction;

[0028]FIG. 4

[0029] (a) is a perspective view of the embroidering frame of the invention;

[0030] (b) is a side elevational view of the embroidering frame shown as being partly movable;

[0031] (c) is a side elevational view of the embroidering frame mounted to the carriage shown partly in vertical section;

[0032]FIG. 5

[0033] (a) is a perspective view of another embodiment of the embroidering frame of the invention;

[0034] (b) is an enlarged side elevational view of the essential parts of the embroidering frame shown in vertical section;

[0035] (c) is an enlarged side elevational view of another embodiment of the essential parts of the embroidering frame shown in vertical section;

[0036] (d) is a side elevational view of the essential parts of the embroidering frame shown as being partly movable;

[0037] (e) is a side elevational view of the embroidering frame mounted to the carriage shown partly in vertical section;

[0038]FIG. 6

[0039] (a) is a side elevational view of the essential parts of the invention showing one condition in case the invention is actually used;

[0040] (b) is a side elevational view of the essential parts of the invention showing another condition in case the invention is actually used;

[0041]FIG. 7

[0042] (a) is a side elevational view of a conventional sewing machine having a carriage and an embroidering frame mounted to the carriage shown partly in vertical section to show one condition of the embroidering frame in actual use;

[0043] (b) is a side elevational view of the conventional sewing machine having a carriage and an embroidering frame mounted to the carriage shown partly in vertical section to show another condition of the embroidering frame in actual use.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0044] The invention will be described in detail in reference to the preferred embodiments as shown in the attached drawings.

[0045] A shown in FIG. 1, a sewing machine C has a hollow base 15 in which there is provided a mechanism for driving an embroidering frame B in X and Y directions. The frame driving mechanism includes a carriage A which is protruded out of the base 15 and removably hold the embroidering frame B at a distal end thereof to move the same on a machine bed 14 in X-Y direction.

[0046] Precisely as shown in FIGS. 2(a) to (c), the carriage A is composed of a carrier 1 and a mount portion A1. The mount portion A₁ is composed of a vertical support plate 2 having a lower end fixedly connected to the distal end of the carrier 1, a mount 3 mounted to the top of the support plate 2 and a spring member 4. The carrier 1 has the opposite end operatively connected to the frame driving mechanism arranged in the base 15 and is protruded out of the base 15. The carrier 1 may be moved by the frame driving mechanism in the direction axially thereof and in the direction that is normal to the axial direction, that is, in X-Y direction.

[0047] The support plate 2 is a rectangular plate made of metal or synthetic resin and has the upper part formed in U-shape to provide a pair of support arms 2 a, 2 a having holes 2 a ₁, 2 a ₁ formed thereat respectively. The mount 3 is formed in one body with an upper mount plate 3 a and lower guide plates 3 b, 3 b which are L-shaped in section having holes 3 b ₁, 3 b ₁ formed thereat respectively and straddling the support arms 2 a, 2 a of the support plate 2 as shown in FIG. 2(c). The mount 3 with this structure is rotatably connected to the support plate 2 by means of a pair of studs 5, 5 inserted into the respective holes 2 a ₁, 2 a ₁, 3 b ₁, 3 b ₁ respectively.

[0048] As shown in FIGS. 2(b) and (c), the spring member 4 is substantially U-shaped metal plate having one end portion 4 b fixed to the support plate 2 and the opposite swelled end portion 4 a pressed against the mount plate 3 a at the lower side thereof to normally give pressure to the mount plate 3 a to rotate the same clockwise (FIGS. 2(b), 3(a) and (b)) around the support studs 5, 5, thereby to normally incline the same as is progressively lower towards the machine bed 14. Namely, the spring member 4 is provided to act one end of the embroidering frame B to normally press the opposite end part of the embroidering frame B against the bed surface of the sewing machine, thereby to absorb the vibrations of the embroidering frame B which may otherwise be produced during embroidery stitching operation. The spring member 4 may be a compression spring or a torsion spring instead of the above mentioned U-shaped plate spring.

[0049] More precisely, according to the invention, the rotation of the mount 3 around the studs 5, 5 is regulated by a regulating means 6 as shown in FIGS. 3(a) to (d) wherein the positions of the stud 6 a are shown respectively as are regulated by the opening 6 b. The regulating means 6 includes studs 6 a, 6 a having one end portion fixed to the guide plates 3 b, 3 b respectively and the opposite end portion inserted into openings 6 b, 6 b formed at the support arms 2 a, 2 a respectively, the opening 6 b being of an diameter larger than the diameter of the stud 6 a so that the opening 6 b may regulate the angular movement of the stud 6 a, that is, of the mount 3 accordingly.

[0050] The angular regulation region is preferred to be smallest possible so that the angular movement of the mount 3 may be smallest up and down from the horizontal condition of the mount 3. Further, the smallest angular movement regulation of the mount 3 in the clockwise direction in FIGS. 3(a) and (b) will make it easy to mount the embroidering frame B to the mount 3. As to the angular movement regulating means 6, the studs 6 a, 6 a may be fixed to the support arms 2 a, 2 a of the support plate 2 respectively and inserted into the openings 6 b respectively which may be formed at the guide plates 3 b, 3 b of the mount 3 respectively. The support plate 2 and the mount 3 are covered with a cover member 7 to protect the inside structure of the carriage A and to prevent the cloth from being caught by the members of the carriage A.

[0051] Subsequently, the embroidering frame B will be described. The embroidering frame B is substantially composed of a frame 10 for holding a cloth as is extended tightly thereover and an arm 11 having one end fixedly connected to the frame 10 and the opposite free end to be connected to the mount 3. The frame 10 includes an outer frame member 10 a and an inner frame member 10 b which are so assembled as to hold the cloth in cooperation. The arm 11 is provided with a connector 13 at the free end thereof, the connector 13 being a screw having a knob, that is, a thumbscrew which is accessible for securing and removing the embroidering frame B to and from the mount 3 of the carriage A.

[0052] Further, the arm 11 is divided in two portions 11 a, 11 b at the longitudinally intermediate portion thereof, and the two portions 11 a, 11 b are connected to each other with a flexible member 12, that is, a flexible coupling so that the arm portions 11 a, 11 b may be elastically deflected up and down at the flexible member 12 as shown in FIG. 4(b).

[0053] As shown in FIGS. 4(a) to (c), the flexible member 12 is a hinge type flexible coupling having the opposite sides fixedly connected to the opposite ends of the arm portions 11 a, 11 b respectively to normally maintain the arm portions 11 a, 11 b in a horizontal plane. The hinge type flexible member 12 has a center shaft 12 a inserted into a hole 12 b formed as extending axially of the hinge body, so that the arm portions 11 a, 11 b connected to the hinge type flexible member 12 may be pivotally moved around the center shaft 12 b. Namely, the arm 11 is swingable around the center shaft 12 a.

[0054]FIG. 5(a) shows a second embodiment of the flexible member 12 which is a flat elastic plate 12 c having the opposite sides fixedly connected to the opposite ends of the arm portions 11 a, 11 b respectively in a manner as are fixedly inserted into the opposite ends of the arm portions 11 a, 11 b respectively or fixedly connected to the opposite ends of the arm portions 11 a, 11 b respectively at the underside thereof as shown in FIGS. 5(b) and (c), thereby to normally maintain the arm portions 11 a, 11 b in horizontal plane as shown in FIGS. 5(A) and (B), but allow the same to deflect up and down by external force applied thereto as shown in FIG. 5(d).

[0055] In case the embroidering frame B of the flexible member 12 according to the second embodiment is use, the mount 3 of the carriage A is fixedly connected to the top of the support plate 2 instead of being rotatable thereat as shown in FIG. 5(e). In this case, the surface 3 c of the mount 3 is inclined as is progressively lowered towards the sewing machine bed 14 so that the embroidering frame B, that is, the frame 10 (10 a, 10 b) may be pressed against the surface of the sewing machine bed 14 by the elastic force of the flat elastic plate 12 c when the embroidering frame B is mounted to the mount 3 of the carriage A by means of the thumbscrew 13.

[0056] With the carriage A and the embroidering frame B being structured as described above, in case the embroidering frame B is mounted to the mount 3 of the carriage A by means of the thumbscrew 13 located at the free end of the arm 11 of the embroidering frame B while the frame 10 (10 a, 10 b) secured to the opposite end of the arm 11 is placed on the machine bed 14 as shown in FIGS. 1 and 3(a), the frame 10 (10 a, 10 b) of the embroidering frame B is pressed against the surface of the machine bed 14 by the elastic force of the elastic member 4 having a predetermined suitable force which will allow the embroidering frame B to smoothly and steadily move in X-Y direction on the machine bed 14.

[0057] Since the mount 3 is prevented from rotation exceeding a predetermined angular region by the regulating means 6, the frame 10 (10 a, 10 b) of the embroidering frame B may be placed on the surface of the machine bed 14 with an optimal pressure applied thereto which is not so strong as to brake the movement of the embroidering frame B. Further, since the mount 3 is so formed as to slightly incline as is progressively lower towards the machine bed 14, the embroidering frame B may be easily mounted to the mount 3 in spite of the inclination.

[0058] Further, in case the embroidering frame B has the elastic member 12 provided at the arm 11 thereof and is mounted to the mount 3 fixedly connected to the support plate 2 of the carriage A and inclined as is progressively lower towards the machine bed 14 as shown in FIGS. 4(c) and 5(e), the frame 10 (10 a, 10 b) of the embroidering frame B may contact the surface of the machine bed 14 in parallel with each other without a gap appearing theresetween because the arm portion 11 a may be deflected up due to the elasticity of the elastic member 12 while pressing the frame 10 (10 a, 10 b) against the surface of the machine bed 14.

[0059] As is described above, according to the invention, the sewing machine is provided with a means for driving in X-Y direction relative to a vertically reciprocating needle an embroidering frame B having a cloth held thereon to be stitched and a means for pressing the embroidering frame against the surface of the machine bed 14. Therefore, the embroidering frame B may be moved in X-Y direction while the same is pressed against the surface of the machine bed 14 with a suitable force which will allow smooth and steady movement of the embroidering frame B instead of braking the movement of the same, without vibration and/or floating up from the surface of the machine bed 14 which may otherwise be caused during embroidery stitching operation.

[0060] The invention being thus described, it will obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications are intended to be included within the scope of the following claims. 

What is claimed is:
 1. A sewing machine having a function for damping the vibrations of an embroidering frame having a cloth held thereon to be stitched, said sewing machine comprising a drive mechanism for moving said embroidering frame, means for holding said embroidering frame and operatively connected to said drive mechanism to be moved thereby to move said embroidering frame in X-Y direction relative to a vertically reciprocating needle on the surface of a machine bed, and means for absorbing the vibrations of said embroidering frame which may be caused during embroidery stitching operation.
 2. The sewing machine as defined in claim 1, wherein said vibration absorbing means is so formed as to press said embroidering frame against the surface of said machine bed.
 3. The sewing machine as defined in claim 1 or 2, wherein said vibration absorbing means includes a spring means provided in connection with said frame holding means and normally pressing down said embroidering frame.
 4. The sewing machine as defined in claim 1 or 2, wherein said vibration absorbing means includes a member for providing an inclined surface and said embroidering frame is provided with a spring means for pressing said embroidering frame against the surface of said machine bed in cooperation with said inclined surface.
 5. An embroidering frame having a function for damping the vibrations thereof and used in combination with a sewing machine having a drive mechanism for moving said embroidering frame, means for holding said embroidering frame and operatively connected to said drive mechanism to be moved thereby to move said embroidering frame in X-Y direction relative to a vertically reciprocating needle on the surface of a machine bed, said embroidering frame comprising a frame portion for holding a cloth thereon to be stitched and an arm portion having one end fixedly connected to said frame portion and the opposite end connected to said frame holding means, and means for pressing said frame portion against the surface of said machine bed.
 6. The embroidering frame as defined in claim 5, wherein said means for pressing said frame portion against the surface of said machine bed includes a mechanism including a flexible member allowing said arm portion to rotatingly move to adjustably press frame portion against the surface of said machine bed.
 7. The embroidering frame as defined in claim 6, further comprising means for regulating the rotation movement of said arm portion.
 8. The embroidering frame as defined in claim 6 wherein said flexible member is an elastic flat plate. 